Toggle native split views when clicking on the plots icon in the EXPs view

[maxagin]

We want to try to educate the user to use both views when working on an extension. Or at least to understand how we notify about the cross changes in both views.

The same will be done for the EXPs icon in the Plots view (it's coming and will replace the current ribbon. Check here for more details: https://github.com/iterative/design/issues/29)